STIs & testing
Why did trichomoniasis come back after treatment?
Possible reasons symptoms or a positive test return, and why clinical follow-up and partner care matter.
Short answer
Trichomoniasis can seem to return because of reinfection from an untreated partner, a problem with taking treatment as prescribed, or less commonly because treatment did not work as expected. Symptoms can also have another cause. Do not restart, share, or change medicines on your own. Contact the clinician or service that treated you for testing and advice.
Reinfection is common enough to plan for
Partners may have no symptoms but still carry the infection. When one person is treated and a partner is not assessed or treated as advised, it can pass back and forth. That is a health issue to solve, not proof of blame.
Symptoms do not confirm the cause
Discharge, itching, odour, or burning can be caused by several conditions. A test is needed to work out whether trichomoniasis is present again. Tell the service when treatment ended, whether sex occurred afterwards, and what symptoms you have now.
Follow the service’s return-to-sex advice
Ask when you and partners can safely resume oral, vaginal, or anal sex, and whether repeat testing is recommended. This reduces avoidable reinfection and gives a clear plan rather than relying on symptoms.
Seek prompt assessment for severe symptoms
Pelvic pain, fever, pregnancy, testicular pain or swelling, rapidly worsening symptoms, or feeling very unwell deserve prompt medical care.
Sources and further reading
- CDC: Trichomoniasis treatment guidelines (accessed August 2026)
- CDC: Retesting after treatment to detect repeat infections (reviewed July 22, 2021)